Keywords
dizziness - aging - nutrition
Introduction
            The elderly are at risk for nutritional disorders and malnutrition, including undernutrition
               and nutrient deficiencies and imbalances. Several age-related physical, clinical,
               economic, and social factors can compromise nutritional status; furthermore, changes
               in the body composition of elderly people and sedentary lifestyles reduce energy requirements
               and daily energy intakes. The highly intercorrelated nature of the consumption of
               dietary components makes it difficult to evaluate specific unconfounded effects through
               observational studies.[1]
               [2]
               
            Eating patterns have been considered risk factors for various metabolic and circulatory
               changes that cause several symptoms including dizziness, especially among elderly
               individuals.[3]
               [4] Dizziness is a change in balance characterized by the illusion of movement of the individual
               or the environment that surrounds them. Rotational dizziness is called vertigo.[5] This symptom is highly prevalent worldwide, affecting ∼2% of young adults, 30% at
               65 years, and up to 50% in the elderly over 85 years.[6]
               
            Especially in the elderly, a lack of regular physical activity, low level of physical
               fitness, and nutritional disorders are risk factors for several metabolic and circulatory
               changes that cause various symptoms, such as dizziness and even benign paroxysmal
               positional vertigo (BPPV).[1]
               [7]
               
            Current evidence shows that good dietary habits in the elderly can improve their quality
               of life. The prevalence of malnutrition is increasing in this population and is associated
               with declines in functional status, impaired muscle function, decreased bone mass,
               immune dysfunction, anemia, reduced cognitive function, poor wound healing, delayed
               recovery from surgery, higher hospital readmission rates, and mortality.[8]
               
            
               Malnutrition is defined as a state in which a deficiency, excess, or imbalance of energy, protein,
               and other nutrients causes adverse effects on body form, function, and clinical outcome.[9]
               
            There is evidence to suggest that dietary habits such as low sodium can alter inner
               ear fluid homeostasis and auditory function. The experiments indicate that the endolymph
               compartment has a built-in mechanism for maintaining a low-sodium concentration while
               keeping ionic balance with the surrounding perilymph and serum.[10]
               
            The labyrinth system, which depends on a continuous supply of energy, is influenced
               by the circulating levels of glucose and hormones, which depend on the generation
               of energy by adenosine triphosphate. Data in the literature estimate that the occurrence
               of glucose metabolic disorder is between 42 and 80% in patients with tinnitus and
               dizziness, whereas 2.5 to 15% of the population presents asymptomatic hypoglycemia
               or some affection of glucose tolerance curves. In Brazil, glucose metabolic disorder
               has already been considered the most frequent cause of labyrinthic metabolic dysfunctions.[11]
               [12]
               
            Vertigo is the most common type of dizziness and BPPV is the most common cause of
               vertigo in adults. It has an estimated prevalence of 3.2% in women and 1.6% in men.
               It is considered the most common cause of dizziness in the elderly, and 30% of people
               had the condition at least once.[13]
               [14]
               
            In the United States, BPPV has an estimated prevalence of 2.4% in the general adult
               population, and although this disorder affects people throughout life, it tends to
               affect individuals aged 50 to 70 years and therefore affects payroll taxes and the
               health.[15]
               
            Based on the considerations presented, this study aimed to investigate the possible
               association between the presence of BPPV with the practice of food habits in the elderly.
         Methods
            This cross-sectional study was approved by the Human Research Ethics Committee.[16] It is part of a broader investigation, the EELO Project (from Portuguese: studies
               on aging and longevity), which has been conducted in Londrina since 2009. The city
               of Londrina (∼500,000 inhabitants) is situated in the north region of Paraná state,
               Brazil. The city has a population of 43,610 elderly people enrolled in the 38 primary
               care units in the urban city area. The sample was a randomly stratified set, considering
               the gender and the five regions of the city (15% from the central region, 27% from
               the northern region, 23% from the southern region, 19% from the eastern region, and
               16% from the western region). The study included individuals aged 60 years and over,
               of both genders, who were living independently and classified at level 3 or 4 as proposed
               by Spidurso.[17] This classification evaluates the independence level of the elderly, with level
               1 indicating a lack of self-mobility and level 5 indicating athletes. Elderly who
               had any illness or limitation that would prevent the testing, such as physical or
               mental disabilities, were excluded from the sample. All the participants signed an
               informed consent form. Four hundred ninety-six subjects were included in this part
               of the study. BPPV was found in 117, and 53 of them had recurrent BPPV confirmed by
               the questionnaire.
            The dietary information was collected by means of the dietary 24-hour recall methods.[18] The interviews were conducted on three different days: one day on the weekend and
               two in the middle of the week. With the aid of photo album with pictures of portion
               sizes and foods, the interviews took place with notation of the food consumed in the
               order of dialed meals. The types of food, the quantities consumed, and how they were
               prepared were recorded. The quantities of these foods were reported in household measures
               and converted into grams or milliliters. Dietary data were processed and analyzed
               with the nutritional evaluation software Avanutri online.[19] The analysis of dietary intake of protein, carbohydrate, lipid, fiber, and cholesterol
               took into account the recommended dietary reference intakes.[20]
               
            The presence of vertigo was established through questions about vertigo (attacks,
               symptoms, and familiar history of vertigo), and the diagnosis of BPPV among study
               participants with vertigo was established with the Dix-Hallpike maneuver and answers
               on the questionnaire about vertigo.[21]
               
            The chi-square test was performed, and p ≤ 0.05 was considered statistically significant. The significance of food habit variables
               and the variables carbohydrates, polyunsaturated fat, monounsaturated fat, saturated
               fat, lipids, protein, and fiber were all considered.
         Results
            Based on a sample of 487 subjects, 117 had BPPV and 370 did not. Of 117 elderly patients
               with BPPV, 37 (31.62%) had inadequate nutrition. Of the 370 without BPPV, 97 (26.21%)
               had inadequate nutrition.
            We did not observe a significant association (p = 0.3064) between food habits and BPPV in the total population (odds ratio =1.3017;
               [Table 1]).
            
               
                  Table 1 
                     Full distribution of the number of patients with BPPV and food habits
                     
                  
                     
                     
                        
                        | Food habits | BPPV | 
                     
                     
                        
                        | Yes (%) | No (%) | 
                     
                  
                     
                     
                        
                        | Inadequate nutrition | 37 (31.62) | 97 (26.21) | 
                     
                     
                        
                        | Adequate nutrition | 80 (68.37) | 273 (73.78) | 
                     
                     
                        
                        | Total | 117 | 370 | 
                     
               
               
               
               Abbreviation: ARR, absolute risk reduction; BPPV, benign paroxysmal positional vertigo;
                  NNH, number needed to harm.
               
               
               Note: Odds ratio = 1.3017; confidence interval 0.8272–2.0483; ARR = 5.41%; NNH = 19;
                  χ2
                  corr = 1.303 (p = 0.3064).
               
                
            
            
            Of the 117 people who had BPPV, 102 (87.17%) had inadequate carbohydrate intake and
               15 (12.82%) did not. And of the 370 people without BPPV, 330 (89.18%) had inadequate
               carbohydrate intake and 40 (10.81%) had normal intake. The Mann-Whitney test was used
               for statistical analysis between inadequate carbohydrates and BPPV and gave a value
               of U = 19,351.50 and p = 0.0419, a statistically significant difference (see [Table 2]).
            
               
                  Table 2 
                     Full distribution of the number of patients with BPPV and inadequate carbohydrate
                        consumption
                     
                  
                     
                     
                        
                        |  | BPPV | 
                     
                     
                        
                        | Inadequate carbohydrates | Yes (%) | No (%) | 
                     
                  
                     
                     
                        
                        | Yes | 102 (87.17) | 330 (89.18) | 
                     
                     
                        
                        | No | 15 (12.82) | 40 (10.81) | 
                     
                     
                        
                        | Total | 117 | 370 | 
                     
               
               
               
               Abbreviation: BPPV, benign paroxysmal positional vertigo.
               
               
               Note: U = 19351.50 (p = 0.0419).
               
                
            
            
            Of the 117 people who had BPPV, 82 (70.08%) had polyunsaturated fat intake and 35
               (29.91%) did not. Of the 370 people without BPPV, 289 (78.10%) had polyunsaturated
               fat intake and 81 (21.89%) did not. For statistical analysis between polyunsaturated
               fat and BPPV, we performed the Mann-Whitney test, which gave a value of U = 18470.00 and p = 0.0084, a statistically significant difference (see [Table 3]).
            
               
                  Table 3 
                     Full distribution of the number of patients with BPPV and diet rich in polyunsaturated
                        fatty acids
                     
                  
                     
                     
                        
                        |  | BPPV | 
                     
                     
                        
                        | Polyunsaturated fat | Yes (%) | No (%) | 
                     
                  
                     
                     
                        
                        | Diet rich in polyunsaturated fatty acids | 82 (70.08) | 289 (78.10) | 
                     
                     
                        
                        | Normal diet in polyunsaturated fatty acids | 35 (29.91) | 81 (21.89) | 
                     
                     
                        
                        | Total | 117 | 370 | 
                     
               
               
               
               Abbreviation: BPPV, benign paroxysmal positional vertigo.
               
               
               Note: U = 18,470.00 (p = 0.0084).
               
                
            
            
            We did not observe a significant association between inadequate protein intake (p = 0.78), inadequate intake of saturated fats (p = 0.97), inadequate intake of lipids (p = 0.43), and inadequate intake of monounsaturated fats (p = 0.79), but there was important significance between BPPV and inadequate fiber intake
               (p = 0.03; [Table 4]).
            
               
                  Table 4 
                     Frequency of BPPV in relation to inadequate intake of protein, saturated fats, monounsaturated
                        fats, lipids, and fibers
                     
                  
                     
                     
                        
                        | Inadequate nutrition | BPPV, n (%) | No BPPV, n (%) | 
                              p Value
                               | 
                     
                  
                     
                     
                        
                        | Inadequate protein[a]
                               | 101 | 325 | 0.7 | 
                     
                     
                        
                        | Inadequate saturated fat[b]
                               | 117 | 368 | 0.97 | 
                     
                     
                        
                        | Inadequate lipids[c]
                               | 35 | 95 | 0.43 | 
                     
                     
                        
                        | Inadequate monounsaturated fat[d]
                               | 82 | 266 | 0.79 | 
                     
                     
                        
                        | Inadequate fiber[e]
                               | 117 | 356 | 0.03 | 
                     
               
               
               
               Abbreviation: BPPV, benign paroxysmal positional vertigo.
               
               
               a χ2
                  corr =0.186.
               
               
               b G (Yates) = 0.010.
               
               
               c χ2
                  corr = 0.816.
               
               
               d χ2
                  corr = 0.142.
               
               
               e G (Yates) = 4.624.
               
                
            
            Discussion
            In this study, we observed the association of BPPV with a diet of inadequate carbohydrate
               intake, rich in polyunsaturated fatty acids, and insufficient fiber intake.
            The elderly often have reduced appetite and energy expenditure, which can occur along
               with a decline of biological and physiological functions, reduction of lean body mass,
               and changes in cytokine and hormonal levels. Other disturbances include changes in
               fluid electrolyte regulation, delayed gastric emptying, and diminished senses of smell
               and taste. In addition, pathologic changes of aging such as chronic diseases and psychological
               illness can lead to bad nutrition in the elderly. Nutritional assessment is important
               to identify, along with treating patients at risk.[8]
               
            Vertigo, tinnitus, and hearing loss are common complaints among the elderly in industrial
               countries. Numerous agents are known to incite vertigo, tinnitus, and hearing loss,
               such as hyperinsulinemia and hyperlipidemia. According to the study of Kaźmierczak
               and Doroszewska,[22] who assessed the occurrence of hyperinsulinemia and hyperlipidemia in patients suffering
               from vertigo, tinnitus, or hearing loss of unknown origin, only hyperlipoproteinemia
               did not differ between patients and control subjects. However, the authors concluded
               that disturbances of metabolism by glucose, such as diabetes mellitus and hyperinsulinemia,
               may be responsible for inner ear diseases, whereas the disturbance of lipid metabolism
               remains vague. Micronutrient insufficiency and high saturated fat intake have been
               associated with chronic diseases.[23] The study also reported that disturbances of glucose may be responsible for inner
               ear diseases.[23] We also detected an excess of carbohydrates; these nutrients are interconvertible,
               raising each other through degradation of its components: 85% excess carbohydrate
               becomes fats (lipids) in the individual by the liver, increasing the lipids, cholesterol,
               and triglycerides in the blood, which may cause accumulation of sodium and potassium
               in the inner ear.
            Huffman et al confirmed our data showing that a lack of fiber leaves the human body
               unprotected, without the minimum number of regulators provided by a good diet.[23] Fiber has an effect on lipid metabolism (propionate) and glucose (acetate, propionate,
               and butyrate), delaying absorption of glucose and starch hydrolysis, helping to maintain
               electrolyte balance of blood capillaries and also assisting the vestibule-cochlear
               apparatus health.
            British dietary recommendations are to decrease total fat intake to less than 30%
               of daily energy consumption and saturated fat to less than 10%. The energy and fat
               intake seems to be reduced on the diet rich in polyunsaturated fatty acids. Insulin
               sensitivity and plasma low-density lipoprotein cholesterol concentrations are improved
               with a diet rich in polyunsaturated fatty acids compared with the diet rich in saturated
               fatty acids.[24] However, other literature has reported that the elderly interviewed in large urban
               centers of Brazil have not joined the new trend of developed countries; consumption
               of traditional foods were replaced by processed foods of easy preparation causing
               dyslipidemia and excess of sodium, damaging the natural physiology chemical level
               in the inner ear among other comorbidities.[25]
               
            In this study, we detected a diet high in polyunsaturated fatty acids ([Table 3]). Reviewing the literature, we could observe that polyunsaturated fatty acids, when
               processed (hydrogenated), can be transformed into trans fats, which are harmful to
               health. However, we cannot analyze this information by itself; an individual who consumes
               excess fat (even good fat) and carbohydrates can still eat a low concentration of
               dietary fiber, which is likely to have dyslipidemia affects in the ear. Even though
               not much data regarding disorders of lipid metabolism exist in the literature, the
               ingestion of high amounts of polyunsaturated fats and trans fat could be related in
               part to lipid metabolism disorders.[26]
               
            Mantello et al wrote that the changes in glucose metabolism are the main metabolic
               changes that lead to vestibulocochlear disorders.[27] As the labyrinthine structures possess an intense metabolic activity, glucose is
               necessary for energy production and for maintaining proper concentrations of sodium
               and potassium in the endolymph.[27] Some habits, such as alcohol, tobacco, sugar, salt, saturated fats, and caffeine,
               in addition to physical inactivity, should be banned from the lives of patients with
               vertigo because they can exacerbate symptoms of cochleovestibular and make vestibular
               compensation even slower.[28] We suggest that the same procedures are taken in cases of BPPV, intensely studied
               here, for the same reasons cited above.
            Through these results, we emphasize the importance of a multidisciplinary care team,
               expanding the procedures and results to prevention and treatment and minimizing episodes
               of recurrent BPPV in the elderly.
         Conclusion
            The association between BPPV with inadequate carbohydrate intake and a diet rich in
               polyunsaturated fatty acids and inadequate fiber intake has been observed. These associations
               deserve more in-depth study.
            These data represent an important tool for better understanding the overall health
               and comorbidities of the elderly, assisting with the reasoning and awareness of a
               necessary change in their lifestyle; through guidelines and nutritional treatments,
               alongside multidisciplinary care, the team can help to decrease hearing symptoms of
               BPPV.
            This study showed the importance of further studies associating the relationship between
               BPPV and the types of food habits. Further research is needed to develop a prevention
               and rehabilitation of BPPV with associate food habits.